In his own words, "This page links to various Linux performance material I've created, including the tools maps on the right, which show: Linux observability tools, Linux benchmarking tools, Linux tuning tools, and Linux observability sar. For more diagrams, see my slide decks below."

His diagram reminds me of Edward Tufte's work on elegant visual explanations. Give it a read, bookmark it, and show your friends. While you're at it, be sure to take a look at OTN's resources for Oracle Linux.